Safety guard for power presses



Dec. 31, 1929. w. 0. w|| ET AL SAFETY GUARD FOR POWER PRESSES Filed June 1, 1926 7 L7 z'z gess. 5;

Patented Dec. 31, 1929 P ori WALTER O. WILL AND ERIC CARLSON, OF CHICAGO, ILLINOIS, ASSZGNORS T0 STEVTART MANUFACTURING CORPORATION, OF CHICAGO, ILLINOIS, A CORPORATION OF DELA- WARE SAFETY GUARD FOR POWER PRESSES Application filed June 1,

The purpose of this invention is to provide a safety device for attachment to punch presses for preventing the hands of the operator from becoming involved between the punch and die in the operating stroke of the punch. It consists in the elements and features of construction shown and described, as indicated in the claims.

In the drawings Figure 1 is a side elevation of a punch press equipped with this invention, the upper and lower part of the press being broken away to condense view.

Figure 2 is a front elevation of the same upon a larger scale.

Figure 3 is a similar View showing the parts embodying the invention in a different position from that of Figure 2.

Figure 4 is a section at the line 4-4 on Figure 2.

In the construction shown in the drawings, the standard of a punch press is indicated at 10. The bed of the press upon which the die is to be mounted is indicated at 11. 12, 12 are similar brackets ri idly secured to the fixed head of the press standard indicated at 13, and projecting forwardly from said head past the path of reciprocation of the punchcarrying press head which is indicated at 15. Upon the press head there is mounted a rack bar, 16, having at its opposite edges parallel racks, 16 16*, which engage respectively gca r segments, 17, 17. having rock shafts, 18, 18, journalled as hereinafter more particularly described upon the brackets, 12, 12, respectively above the Zone of normal position and movement of the operators hands and arms in attending the press. Each of the segments, 17, 17, carries a fender arm, 19, which is mounted for vertical adjustment as hereinafter more particularly described in the segment, said fender arms, 19, 19, extending down and toward each other at their position of rest in front of the path of cooperation of the punch and die, that is to say, between the position of the operator facing the press and the path of movement of the punch, said fender arms at their free ends standing, at their meeting position, substantially across the plane of meeting of the punch and 1926. Serial N0. 112,865.

die; so that said fender arms, 19, project between the position of the forearms, or between the hands of the operator manipulating the metal 1 ween the punch and die. At this rest position of the fender arms, the gear segn'ients, 17, 17, are meshed at their lower ends their respective arcs with the respectively facing racks, 16 16 and in the descending operating stroke of the reciprocating press head, it will be seen that the ra ch, 16, actuates the seglneni's for rocking them in their journal bearings in the direction for spreading the fender arms, 19, 19, at their free ends which stand between the forearms of the operator; whereby the operators hands will be forcibly withdrawn from posi tion at which they would be liable to be involved between the punch and die in the com pletion of the operating stroke of the punch.

Details of the construction will now be described.

The brackets, 12, 12, constitute parts of a rigid and substantially unitary frame Which is carried rigidly on the fixed head, 13, said frame comprising said brackets and a transverse bar. 12, which connects them at their forward ends. said bar being welded to said forward ends of the brackets. At the lap and junctions of said transverse bar, 12, with the brackets, 12, there are secured rigidly to both said lapping parts by welding thereto, journal bearings, 12, 12 for rock shafts, 18, 18, of the segments, 17. Each of the segments, 17, has formed integrally With it at the outer side of the rock shaft, a sleeve, 17 for receiving the upper straight portion, 19 of the fender arm, 19, said fender arm being threaded at said straight portion for adjusting and stop nuts, 20, 20, applied on said threaded portions respectively, above and below the sleeves, 17", the ends of said sleeves being counter-bored for seating the nuts, which are tapered at their inner ends for so seating at the ends of the sleeves. This expedient, it will be seen, constitutes means for adjusting the fender arms, 19, up and down to vary the position of their free end portions which are to guard the hands of the operator. Said free end portions of the fend er arms, 19, are preferably flexed in curved form concave outwardly, that is, toward the arms of the operator; and snbtending the curves at the concave side, there is mounted upon each tender arm a strap, 21, of suitable material such as leather for uninjurious encounter with the arm or hand of the operator in the spreading movement of said guard fender arms, 19.

For inclosing the operating mechanism aprising the segments, 17, for safety, against engagement of the lingers of the operator or bystanders between the rack and said segments, there provided a casing, 25, of comparative l" it sheet metal formed of a blank having iatcral lugs. 26, 2G, 'Eolded at right angles to ti plane ot the bla k l min 1 bracket arms spaced apart by dimension or the b tioned torlapping out respectively. Zhe central or mam body of the blank constituting the front plate of the casing has bayonet-slot apertures 28, E28, and he structure comprising the brackets, 12, is furnished with headed means for engaging the bayonet-slots, the heads passing through the large portion of the slot and the reduced portion back of the heads engaging the narrow portion of the slot When the casing applied in the obvious manner. In the construction as shown, the headed means for engaging the bayonet-slots is afforded by the rock shafts, 18. of the segments, 1?, respectively. said rock shafts being terminated at their forward ends as seen with heads, 18 back of which the rock shafts are reduced in diameter, as indicated at 18. The casing is further adapted to be secured to the brackets bv bolts. 2T, 27, taking through apertures in the lateral lugs, 26, into the brackets 12.

l. In a power press having a bed for holding a die, a hired head and a reciprocating h -d, a device tor the purpose indicated complzs lig a pair of parallel racks mounted on the reciprocating head ot the press; segment gear members pivoted on the lined head of the press for meshing with the respective racks: tender arms mounted on the segments gear inembe respectively and extending in general up and down at the rest position of the reciprocating head with their lowe parts dz'tlected inwardly toward each other and substantially meeting in front or" the position of a die on the bed, the segment gear members bein singularly limensioned with respect to the stroke of the reciprocating head of the press for spreading said fender arms during the down stroke of the reciprocating heed nith v and in excess of the Width of the press.

In a power pr ss having a fixed bed, a lined head and a eciprocating head, a pair of parallel racks iounted on the reciprocat ing bead. segment gear members pivoted on the fixed head of the press at opposite sides of the path of the reciprocating head and ieshing with the respective racks, said ment gear members having adjacent their pivots respectively vertical slideways, fender arms having str i 'ht upper end portions engaged in said slideways, respectively, and having their lower end portions deflected obliquely toward the medial vertical plane oi the path of the reciprocating head, and means for adjusting the fender arms longitudinally of their straight portions in their respective slideways.

1 3. In the construction defined in claim 2, tile upper-end portions or" the tender arms 1and segment gear meni- G M4 eways in which sald straight Fiction:- may be adjust-ed lcngitudinallv, aid night portions being exterior-iv screwtnreaded and having each a longitudinal groove for recei viug a key to hold said fender arms nonrotatbly in the riidcwavs, a key eugaging each of the grooves oi said slidewavs, and nuts on the threaded portions of the tendor arms adapted to be set up against the opposite ends of the slidewavs. whereby thev serve fol-adjusting the tender arms lon gjitndinallv and securing the latter in adjusted position in the slideways. I

in testimony whereof, we have hereunto set our hands at Chicago, Illinois, this 28th day of Elay, l926. I 

